Management asked me to prank.
Back in the day when our venerable coding sheets and punch room were being replaced by 3270s on every desk, we were supposed to lock our machines when we walked away, which we didnt.
Threats and punishment couldn't do the trick so my PM asked me to write a script that would be mapped to the F3 (save) key. It was to do a line by line ascii art middle finger salute with a 10 second delay between lines with a reminder to log off ... after it did the save it should do. Hapless dev walks away pm remaps f3 to 'the finger' dev returns no sign until he (and we were all hes) goes to save his work, and 10 minutes later has access to his machine again. A week later the leaving machines unlocked problem was solved.